Sheath assembly for ultrasonic probe

ABSTRACT

A sheath assembly is adapted for an ultrasonic probe and includes a plug portion and a sheath portion connected to each other. One end of the plug portion of the sheath assembly is used for detachably and fixedly connecting with a connecting butt joint portion of the ultrasonic probe, so that the plug portion and the connecting butt joint portion are detachable after the ultrasonic probe is used.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation application of and claims the priority benefit ofa prior application Ser. No. 16/611,479 filed on Nov. 7, 2019, nowpending. The prior application Ser. No. 16/611,479 is a 371 applicationof the International PCT application No. PCT/CN2019/087865 filed on May21, 2019, which claims the priority benefit of China application serialno. 201910409931.X, filed on May 16, 2019. The entirety of theabove-mentioned patent applications are hereby incorporated by referenceherein and made a part of this specification.

BACKGROUND Technical Field

The present invention relates to the technical field of medicalinstruments, and more specifically, to a sheath assembly, an ultrasonicprobe and an assembling method thereof.

Description of Related Art

Ultrasound endoscope is a commonly used medical instrument, and itsultrasonic probe can enter the organ of the human body to be examinedthrough the natural cavity of the human body, such as a urinary tract ora surgical incision, and directly peep into the lesion of the relevantpart, to assist in obtaining clear images.

A fiber-optic ultrasound endoscope in an ultrasound endoscope has anelongated ultrasonic probe that allows an ultrasonic transducer attachedto one end of the ultrasonic probe to penetrate deep into the humanbody. In addition, the ultrasonic transducer is connected to the driverof the other end of the ultrasonic probe and the imaging system througha coaxial cable. Driven by an external motor, the ultrasonic transducermay be free to rotate within the ultrasonic probe to create a circularor cross-sectional image of the tissue section perpendicular to theaxial direction.

However, most fiber-optic ultrasound endoscopes in the prior art areintegral structures. Due to the high cost of ultrasonic transducers,after each clinical application process, the part of the ultrasonicprobe that directly contacts the human tissue is cleaned anddisinfected, and then continues to be used for the next clinical use,which is prone to cause the problem of cross-infection. Also, thepractice of abandoning the entire ultrasonic probe after each clinicalapplication has resulted in a significant increase in treatment costs.

Therefore, it is necessary to develop a new type of ultrasonic probe toavoid the above problems in the prior art.

SUMMARY

It is an object of the invention to provide a sheath assembly, anultrasonic probe having the sheath assembly, and an assembling method ofthe ultrasonic probe, so as to avoid the problem of prone to crossinfection caused by the overall repetitive use of the ultrasonic probein the prior art while reducing the cost of treatment.

To achieve the above object, the sheath assembly of the inventioncomprises a plug portion and a sheath portion, and one end of the plugportion is used for detachably and fixedly connecting with a connectingbutt joint portion of the ultrasonic probe. The other end of the plugportion is fixedly connected to one end of the sheath portion, and aninside of the plug portion communicates with an inside of the sheathportion to receive a torque transmitting portion of the ultrasonicprobe.

The sheath assembly of the invention has the following beneficialeffects: one end of the plug portion is used for detachably and fixedlyconnecting with a connecting butt joint portion of the ultrasonic probe,so that the plug portion and the connecting butt joint portion aredetachable after the ultrasonic probe is used. Therefore, on the onehand, the connecting butt joint portion to which the torque transmittingportion is fixed is retained for subsequent application process tofacilitate reducing treatment costs; on the other hand, the used sheathassembly may be directly discarded due to its direct contact with humantissue and low cost, thereby avoiding cross-infection problems caused byrepeated use.

Preferably, the plug portion comprises a recess, and an inner sidewallof the recess has a first threaded structure to effect the detachablyfixed connection with the connecting butt joint portion through threadedengagement. The beneficial effects include: the detachably fixedconnection of the plug portion and the connecting butt joint portion maybe quickly achieved by threaded engagement.

Further preferably, a bottom portion of the recess is provided with afirst locking portion, and an inside of the first locking portioncommunicates with an inside of the sheath portion; an outer sidewall ofthe first locking portion is engageable with an inner sidewall of theconnecting butt joint portion such that the first locking portion isreceived inside the connecting butt joint portion. The beneficialeffects include: it is advantageous to further improve the sealingperformance between the plug portion and the connecting butt jointportion.

Preferably, the first locking portion has a first inner diameter forreceiving the torque transmitting portion, the first inner diameterbeing greater than or equal to 0.5 mm and larger than an outer diameterof the torque transmitting portion. The beneficial effects include: itis advantageous for the torque transmitting portion to be freelyrotatable within the first locking portion to obtain good imageinformation.

Further preferably, the outer sidewall of the first locking portion hasa taper such that the first locking portion is received inside theconnecting butt joint portion and is fixedly connected to the connectingbutt joint portion by taper self-locking.

Further preferably, the taper ranges from 3 degrees to 6 degrees toenable the sheath assembly to withstand at least 1 atmosphere for aperiod of at least 30 seconds. The beneficial effects include: thestrength of the sheath assembly is further increased.

Still more preferably, the plug portion has a sealing portion fordetachably and fixedly connecting to the first locking portion. Thebeneficial effects include: it is advantageous to subsequently injectthe liquid into the sheath assembly for sealing to facilitate storage ortransport of the sheath assembly.

Preferably, the other end of the sheath portion has a sealing headstructure. The beneficial effects include: it is convenient to receivethe liquid in the sheath portion during the subsequent use of theultrasonic probe to facilitate the good signal transmission function ofthe ultrasonic transducer of the torque transmission portion.

Preferably, the sheath portion has a first sheath and a second sheaththat are connected to each other, one end of the first sheath beingfixedly connected to the sheath connecting portion of the plug portion,the first sheath having a Shore hardness greater than that of the secondsheath. The beneficial effects include: the first sheath connected tothe sheath connecting portion has a Shore hardness greater than that ofthe second sheath at the distal end, which is advantageous for enhancingthe strength of the sheath portion and facilitates the sheath portion tobe smoothly pushed in the body; on the other hand, the second sheathhaving a lower Shore hardness directly contacts human tissue, and mayreduce damage to human tissues, which also facilitates bending to entermore complicated and narrow channels.

Further preferably, the sheath portion also has a third sheath, and thethird sheath has a Shore hardness greater than or equal to that of thefirst sheath and is at least partially sleeved outside of the firstsheath to enhance a strength of the sheath portion. The beneficialeffects include: it is convenient for the sheath portion to smoothlycarry out the pushing process in the body.

Still more preferably, one end of the third sheath is fixedly connectedto the sheath connecting portion, and is sleeved outside of the firstsheath, a length of the third sheath is less than that of the firstsheath.

Still more preferably, the first sheath has a Shore hardness of 50D-90D,the second sheath has a Shore hardness of 30D-75D, and the third sheathhas a Shore hardness of 50D-90D.

Still more preferably, the third sheath is a metal spring sleeve, andthe metal spring sleeve is movably sleeved outside of the sheathconnecting portion and the outside of a portion of the first sheath.

The ultrasonic probe of the invention comprises a connecting butt jointportion, a torque transmitting portion, and the sheath assembly. Thesheath assembly has a plug portion and a sheath portion which areconnected to each other. The connecting butt joint portion is detachablyand fixedly connected to the plug portion. A fixed end of the torquetransmission portion is fixedly connected in the connecting butt jointportion, and a transducer end of the torque transmitting portion extendsthrough the connecting butt joint portion and the plug portion to enterthe sheath portion.

The beneficial effects of the ultrasonic probe of the present inventioninclude: the connecting butt joint portion of the ultrasonic probe isdetachably and fixedly connected to the plug portion, so that the plugportion and the connecting butt joint portion are detachable after theultrasonic probe is used. Therefore, on the one hand, the connectingbutt joint portion to which the torque transmitting portion is fixed isretained for subsequent application process to facilitate reducingtreatment costs; on the other hand, the used sheath assembly may bedirectly discarded due to its direct contact with human tissue and lowcost, thereby avoiding cross-infection problems caused by repeated use.

Preferably, the connecting butt joint portion has a first connectingportion, and the first connecting portion has a second inner diameter.The second inner diameter is used for receiving the torque transmittingportion, and the second inner diameter is greater than or equal to 0.5mm and is larger than an outer diameter of the torque transmittingportion. The beneficial effects include: it is advantageous for thetorque transmitting portion to be freely rotatable within the firstconnecting portion to obtain good image information.

Further preferably, the connecting butt joint portion further has asecond connecting portion, and the second connecting portion iscoaxially connected to the first connecting portion detachably andfixedly. A portion of the outer surface of the second connecting portionhas a second threaded structure for locking with the plug portionthrough threaded engagement.

Further preferably, the plug portion has a first locking portion, andthe second connecting portion receives the first locking portion suchthat an inside of the connecting butt joint portion communicates with aninside of the sheath assembly, and an inner sidewall of the secondconnecting portion is fitted to an outer sidewall of the first lockingportion. The beneficial effects include: further improving the sealingperformance between the plug portion and the connecting butt jointportion.

Still more preferably, the inner sidewall of the second connectingportion has a taper to receive the first locking portion, and the secondconnecting portion is connected to the first locking portion by taperself-locking. The beneficial effects include: the strength of theultrasonic assembly is enhanced on the basis of further improving thesealing performance.

Still more preferably, the first locking portion has the Shore hardnessless than that of the second connecting portion. The beneficial effectsinclude: the sealing performance is further enhanced by a combination ofsoftness and hardness.

A method of assembling the ultrasonic probe comprises following steps.

S1: Providing the sheath assembly, a drainage tube and a liquidinjection device, the sheath assembly including the plug portion and thesheath portion which are connected to each other; passing one end of thedrainage tube into a bottom portion of the sheath portion through theplug portion; and injecting a liquid into the sheath portion through theother end of the drainage tube using the liquid injection device.

S2: Providing the connecting butt joint portion with the torquetransmitting portion being fixed thereon, inserting a transducer end ofthe torque transmitting portion from the plug portion into the sheathportion, and then locking the plug portion to the connecting butt jointportion, so as to complete assembly of the ultrasonic probe.

The method of assembling the ultrasonic probe of the invention has thefollowing beneficial effects: since the assembly of the ultrasonic probemay be completed by locking the plug portion to the connecting buttjoint portion, in the subsequent disassembling process, the connectingbutt joint portion to which the torque transmitting portion is fixed isretained on the one hand for subsequent application process tofacilitate reducing treatment costs, and the used sheath assembly may bedirectly discarded on the other hand due to its direct contact withhuman tissue and low cost, thereby avoiding cross-infection problemscaused by repeated use.

Preferably, the plug portion is provided with a sealing portion, in thestep S1, the sealing portion is removed to inject the liquid into thesheath portion through the drainage tube and the liquid injectiondevice.

Preferably, the method further includes step S3. In the step S3, theconnecting butt joint portion and the plug portion are unlocked afterthe ultrasonic probe is used, the sealing structure of the sheathportion is broken, and the connecting butt joint portion is pulled topull the torque transmitting portion away from the sheath assembly. Thebeneficial effects include: after unlocking the connecting butt jointportion and the plug portion, the sealing structure of the sheathportion is broken, so as to pull the connecting butt joint portion topull the torque transmitting portion away from the sheath assembly.

Further preferably, a distal end of the sheath portion has a sealinghead structure, and in the step S3, after the connecting butt jointportion and the plug portion are unlocked, the sealing head structure iscut to break the sealing structure of the sheath portion.

Further preferably, in the step S3, after the connecting butt jointportion and the plug portion are unlocked, an outer sidewall of thesheath portion is destroyed to break the sealing structure of the sheathportion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural view of a first sheath assembly of Embodiment 1of the present invention;

FIG. 2 is a longitudinal sectional view of a plug portion shown in FIG.1 ;

FIG. 3 is a view showing the assembly of a third sheath and a sheathconnecting portion in Embodiment 2 of the present invention;

FIG. 4 is a structural view of a spring sleeve of Embodiment 3 of thepresent invention;

FIG. 5 a is a structural view of a sealing sleeve head of Embodiment 4of the present invention;

FIG. 5 b is an exploded view of another sealing sleeve head ofEmbodiment 4 of the present invention;

FIG. 6 is a structural view of a first ultrasonic probe of Embodiment 5of the present invention;

FIG. 7 is a structural view of a first socket portion shown in FIG. 6 ;

FIG. 8 a and FIG. 8 b are sectional views showing first threadedstructure and second threaded structure are able to be engaged with eachother;

FIG. 9 is a structural view of a torque transmitting portion ofEmbodiment 5 of the present invention;

FIG. 10 is a structural view of a plug portion of Embodiment 6 of thepresent invention; and

FIG. 11 is a longitudinal sectional view of the plug portion shown inFIG. 10 .

DESCRIPTION OF THE EMBODIMENTS

In order to make objectives, technical solutions, and advantages of thepresent invention clearer, the technical solutions in the presentinvention are described clearly and completely in the following withreference to accompanying drawings in the embodiments of the presentinvention. Apparently, the described embodiments are only part ratherthan all of the embodiments of the present invention. Based on theembodiments of the present invention, all the other embodiments obtainedby those of ordinary skill in the art without inventive effort arewithin the scope of the present invention. Unless otherwise mentioned,all technical and scientific terms used herein have the same meaning ascommonly understood by one of ordinary skill in the art to which theinvention belong. “Comprise”, “include” and the like are intended todenote the element or object before the word is included in the listedelement or object and thereof equivalents after the word, instead ofexcluding other elements or objects.

In view of the problems existing in the prior art, embodiments of thepresent invention provide a sheath assembly and a method of preparingthe sheath assembly. The sheath assembly is adapted for an ultrasonicprobe.

The sheath assembly has a plug portion and a sheath portion. A proximalend of the sheath portion is fixedly connected to the sheath connectingportion of the plug portion, and the proximal end is defined as an endadjacent to the plug portion. One end of the plug portion is used fordetachably and fixedly connecting with a connecting butt joint portionof the ultrasonic probe. The sheath connecting portion is fixedlyconnected to one end of the sheath portion, and the inside of the plugportion communicates with the inside of the sheath portion to receive atorque transmitting portion of the ultrasonic probe.

In some embodiments of the present invention, at least a portion of theouter surface of the sheath portion is hydrophilic.

The preparation method for the sheath assembly comprises:

Providing the plug portion and the sheath portion to be processed, andperforming a head sealing treatment on one end of the sheath portion tobe processed to form a sealing head structure.

Performing a hydrophilic treatment on at least a portion of the outersurface of the sheath portion to be processed to form the sheathportion.

Connecting an opening end of the sheath portion fixedly to the sheathconnecting portion of the plug portion to form the sheath assembly.

In some embodiments of the present invention, a hydrophilic treatment isperformed on the at least a portion of the outer surface of the sheathportion to be processed in a radial direction of the sheath portion tobe processed from a distal end point of the sealing head structure as astarting point to form the sheath portion.

In some embodiments of the present invention, the region of the outersurface of the sheath portion to be processed that needs the hydrophilictreatment comprises a region directly in contact with human tissue toenhance biocompatibility of the sheath portion.

Embodiments of the present invention further provide an ultrasonicprobe, and an assembling method of the ultrasonic probe.

The ultrasonic probe comprises the sheath assembly, the connecting buttjoint portion, and the torque transmitting portion. A transducer end ofthe torque transmitting portion is fixed with an ultrasonic transducerwith the other end of the ultrasonic transducer being a fixed end. Thefixed end is fixedly connected inside the connecting butt joint portion.The connecting butt joint portion is connected to the plug portion in adetachably fixed connection, and a transducer end of the torquetransmitting portion extends through the connecting butt joint portionand the plug portion to enter the sheath portion.

The method of assembling the ultrasonic probe comprises:

S1: Providing the sheath assembly, a drainage tube and a liquidinjection device, the sheath assembly including the plug portion and thesheath portion which are connected to each other; passing one end of thedrainage tube into a bottom portion of the sheath portion through theplug portion; and injecting a liquid into the sheath portion through theother end of the drainage tube using the liquid injection device.

S2: Providing the connecting butt joint portion to which the torquetransmitting portion is fixed, inserting a transducer end of the torquetransmitting portion from the plug portion into the sheath portion, andthen locking the plug portion to the connecting butt joint portion, soas to complete assembly of the ultrasonic probe.

In some embodiments of the present invention, a sealing portion is usedto seal the plug portion to seal the liquid inside the sheath assemblyand facilitate the transportation of the sheath assembly.

In the step S1 of some embodiments of the present invention, the plugportion is provided with a sealing portion and the sealing portion isremoved to inject the liquid into the sheath portion.

In some embodiments of the present invention, the connecting butt jointportion and the plug portion are unlocked after using the ultrasonicprobe, the sealing structure of the sheath portion is broken, and theconnecting butt joint portion is pulled to pull the torque transmittingportion away from the sheath assembly.

In some embodiments of the present invention, a distal end of the sheathportion has a sealing head structure, and the sealing head structure iscut to break the sealing structure of the sheath portion.

In some embodiments of the present invention, an outer sidewall of thesheath portion is destroyed to break the sealing structure of the sheathportion. Specifically, the sealing structure of the sheath portion isbroken by opening a through hole in the outer sidewall of the sheathportion or slashing the outer sidewall of the sheath portion.

The technical solutions of the present invention will be described indetail below by way of Embodiments 1-6.

Embodiment 1

The present embodiment provides a first sheath assembly having a firstplug portion and a sheath portion.

FIG. 1 is a structural view of a first sheath assembly of Embodiment 1of the present invention. FIG. 2 is a longitudinal sectional view of afirst plug portion shown in FIG. 1 .

With reference to FIGS. 1 and 2 , the first sheath assembly 1 has afirst plug portion 11 and a sheath portion 12. The first plug portion 11has a first locking portion 111 and a first sheath connecting portion112. The sheath portion 12 has a first sheath 121 and a second sheath122.

With reference to FIGS. 1 and 2 , the first plug portion 11 has acylindrical fixing portion 114. One end of the fixing portion 114defines a first recess 1141, and the first recess 1141 is a cylindricalrecess. The first locking portion 111 has an internal hollow structure,and a passage inside the fixing portion 114 communicates with the insideof the first sheath connecting portion 112 to receive a torquetransmitting portion (not shown). One end of the first locking portion111 is fixed to a bottom portion of the first recess 1141. The firstsheath connecting portion 112 is a hollow structure having an extensiontube 1122 and a conical joint tube 1121 which are sequentiallyconnected. One end of the extension tube 1122 is fixed to the other endof the fixing portion 114, and the conical joint tube 1121 is fixedlyconnected to one end of the first sheath 121. A center line of the firstlocking portion 111 and a center line of the first sheath connectingportion 112 both coincide with a center line 13 of the fixing portion114.

With reference to FIGS. 1 and 2 , the first locking portion 111 is atruncated cone structure, and the longitudinal cross-sectional shapethereof is an isosceles trapezoid. That is, the outer sidewall of thefirst locking portion 111 has a taper shape so as to be received insidethe connecting butt joint portion (not shown), and is fixedly connectedwith the connecting butt joint portion (not shown) by taperself-locking. The manner of taper self-locking is advantageous toenhance the sealability and strength of the ultrasonic probe assembledby the sheath assembly 1. When the sheath assembly 1 is injected withliquid and assembled into the ultrasonic probe, the sheath assembly 1may withstand at least 1 atmosphere for at least 30 seconds withoutcausing the liquid leakage. The taper is a ratio between an absolutevalue of a difference between the lengths of the two base sides of theisosceles trapezoid and a height of the isosceles trapezoid.

In some specific embodiments of the present invention, the taper rangesfrom 3 degrees to 6 degrees. The sheath assembly 1 may withstand atleast 3 atmospheres for at least 30 seconds without causing the liquidleakage.

With reference to FIGS. 1 and 2 , the first sheath 121 is a hollow tubestructure with two open ends, with one end being fixed to the inner wallof a tapered joint of the first sheath connecting portion 112 by anepoxy resin glue, and the other end being fixed to one end of the secondsheath 122 by heat fusion. The distal end of the second sheath 122 is ahemispherical sealing head structure. The inner sidewall of the firstrecess 1141 has a first threaded structure 1142.

In some embodiments of the present invention, the first locking portion111 has a first inner diameter that is greater than or equal to 0.5 mmand larger than an outer diameter of the torque transmitting portion forreceiving the torque transmitting portion. In some specific embodimentsof the present invention, the first inner diameter is any one of 0.5 mm,1.0 mm, 1.2 mm, and 1.4 mm.

In the present embodiment, the first sheath 121 and the second sheath122 have the same inner diameter and the same outer diameter. A lengthof the first sheath 121 is greater than a length of the second sheath122. In some specific embodiments of the present invention, the lengthof the first sheath 121 is 175 cm, and the length of the second sheath122 is 5 cm.

In some embodiments of the present invention, with reference to FIG. 2 ,the sheath portion 12 has only the second sheath 122, and one end of thesecond sheath 122 is fixedly connected to the conical joint tube 1121.

In some embodiments of the present invention, the second sheath 122 is ahollow tube structure with two open ends, that is, the distal end of thesecond sheath 122 does not have the sealing head structure.

In some embodiments of the present invention, the constituent materialsof the first sheath 121 and the second sheath 122 are both plastic. Insome specific embodiments of the present invention, the constituentmaterial of the plastic is polyetheramide elastomer, high densitypolyethylene or nylon.

In the present embodiment, with reference to FIGS. 1 and 2 , the Shorehardness of the first sheath 121 is greater than the Shore hardness ofthe second sheath 122. The first sheath 121 has a Shore hardness of 75 Dand the second sheath 122 has a Shore hardness of 50 D. On the one hand,the first sheath 121 connected to the first sheath connecting portion112 has a Shore hardness greater than that of the second sheath 122,which is advantageous for enhancing the strength of the sheath portion12 and facilitates the sheath portion 12 to be smoothly pushed in thebody. On the other hand, the second sheath 122 having a lower Shorehardness directly contacts human tissue, which may reduce damage to thehuman tissue.

In some embodiments of the present invention, the first sheath 121 has aShore hardness of 50D-90D and the second sheath 122 has a Shore hardnessof 30D-75D. In some specific embodiments of the present invention, thefirst sheath 121 has a Shore hardness of any one of 60D, 70D, 75D, 80D,and 85D, and the second sheath 122 has a Shore hardness of any one of30D, 40D, 45D, 55D, 60D, 65D, 70D, and 75D.

With reference to FIG. 1 , starting from an end point of the sealinghead structure of the second sheath 122, a hydrophilic treatment isperformed along the radial direction of the sheath portion 12 to form ahydrophilic modification layer on at least a portion of the surface ofthe sheath portion 12.

A liquid is injected into the sheath portion using a liquid injectiondevice containing the liquid therein. The liquid injection device has aninjection syringe and a drainage tube, and the inside of the injectionsyringe is filled with the liquid. With reference to FIGS. 1 and 2 , thedrainage tube (not shown) is inserted into the sheath portion 12 via thefirst locking portion 111, and one end of the drainage tube (not shown)is caused to reach a bottom portion of the second sheath portion 122with the other end of the drainage tube extending beyond the firstlocking portion 111. The injection syringe (not shown) is inserted intothe drainage tube (not shown), followed by slowly injecting the liquidinto the sheath portion 12, and the drainage tube (not shown) is slowlypulled out of the first locking portion 111 through the injectionsyringe (not shown) while injecting the liquid, so as to ensure that noair bubbles are generated inside the sheath portion 12. After theinjection of the liquid in the syringe (not shown) is completed, thedrainage tube (not shown) is withdrawn, and the first locking portion111 is then sealed using a sealing portion (not shown).

In the present embodiment, an outer diameter of the drainage tube issmaller than the inner diameter of the first locking portion 111 andsmaller than the inner diameter of the sheath portion 12, and theconstituent material of the drainage tube is plastic.

In some embodiments of the present invention, the liquid injected intothe sheath portion is at least capable of immersing the ultrasonictransducer of the torque transmitting portion to facilitate signaltransmission of the ultrasonic transducer to obtain a clear image.

In some embodiments of the present invention, the liquid is any one ofphysiological saline or silicone oil. The plastic isPolyetheretherketone (PEEK).

Embodiment 2

The present embodiment provides a second sheath assembly which differsfrom the first sheath assembly of Embodiment 1 of the present inventionin that the sheath portion further has a third sheath, which is a hollowtube.

FIG. 3 is a view showing the assembly of a third sheath and a sheathconnecting portion in the embodiment. With reference to FIGS. 1 to 3 ,the outer diameter of a hollow tube 31 is adapted to the diameter of ahollow duct 1133 inside the first sheath connecting portion 112. One endof the hollow tube 31 extends to the inside of the hollow duct 1133, andis adhered and fixed to the inner wall of the conical joint tube 1121 byepoxy glue to be sleeved outside the first sheath 121. One end of thefirst sheath 121 is fixed to the inner wall of the first sheathconnecting portion 112 by epoxy glue or heat fusion. The length of thehollow tube 31 is smaller than that of the first sheath 121.

In some embodiments of the present invention, the outer diameter of thefirst sheath 121 is adapted to the inner diameter of the hollow tube 31.

In the present embodiment, the Shore hardness of the hollow tube 31 isgreater than or equal to that of the first sheath 121. The Shorehardness of the hollow tube 31 is 50D to 90D. In some specificembodiments of the present invention, the third sheath has a Shorehardness of any one of 50D, 60D, 65D, 70D, 75D, and 80D.

Embodiment 3

The present embodiment provides a third sheath assembly. The thirdsheath assembly differs from the second sheath assembly of Embodiment 2of the present invention in that the third sheath is a metal springsleeve. The metal spring sleeve is movably sleeved outside the sheathconnecting portion and a portion of the first sheath to enhance aconnection relationship between the sheath connecting portion and thesheath portion.

FIG. 4 is a structural view of a metal spring sleeve of Embodiment 3.With reference to FIGS. 2, 3 and 4 , a metal spring sleeve 4 has a firstsleeve 41, a tapered sleeve 42, and a second sleeve 43 which aresequentially connected. A length of the first sleeve 41 is equal to alength of the extension tube 1122, and an inner diameter thereof isadapted to the outer diameter of the extension tube 1122. A length ofthe tapered sleeve 42 is equal to the length of the conical joint tube1121, and the shape of the inner wall thereof is the same as the shapeof the outer wall of the conical joint tube 1121. A length of the secondsleeve 43 is smaller than the length of the first sheath 121, and aninner diameter of the second sleeve 43 is adapted to the outer diameterof the third sheath 31. The metal spring sleeve 4 is a movable sleevethat is movable in the radial direction of the first sheath 121.

Embodiment 4

The present embodiment provides a fourth sheath assembly. The fourthsheath assembly differs from the third sheath assembly of Embodiment 3of the present invention in that the fourth sheath assembly further hasa sealing portion which is a sealing sleeve head.

FIG. 5 a is a structural view of a sealing sleeve head of Embodiment 4.With reference to FIGS. 2 and 5 a, the first sealing sleeve 51 is ahollow structure that is open at one end. The outer sidewall of thefirst sealing sleeve head 51 has a first locking thread 511 for engagingthe first threaded structure 1142. The inner sidewall of the firstsealing sleeve head 51 has a taper to receive the first locking portion111, so that the outer sidewall of the first locking portion 111 isfitted to the inner sidewall of the first sealing sleeve head 51 in aself-locking manner. A bottom portion of the first sealing sleeve head51 is fitted to the end surface of the first locking portion 111 to sealthe first locking portion 111.

FIG. 5 b is an exploded view of another type of sealing sleeve head ofEmbodiment 4. With reference to FIGS. 2 and 5 b, a second sealing sleevehead 52 has a sealing tube 521 and a sealing head 522. The sealing plug522 is a cylindrical structure having an intermediate recess (not shown)at one end. A bottom portion of the intermediate recess (not shown) hasa plug 5221.

The sealing tube 521 is a hollow structure that is open at both ends. Aportion of the outer sidewall of one end of the sealing tube 521 has thefirst locking thread 511, and a portion of the inner sidewall thereofhas a taper, so as to receive the first locking portion 111, so that theouter sidewall of the first locking portion 111 is fitted to a portionof an inner sidewall of the second sealing sleeve head 52 in a taperself-locking manner. Another portion of the inner sidewall of thesealing tube 521 is used for receiving the plug 5221, and the innersidewall of the intermediate recess (not shown) is engaged with aportion of the outer sidewall of the sealing tube 521, so that thesealing head 522 is detachably and fixedly connected to the sealing tube521.

Embodiment 5

The present embodiment provides a first ultrasonic probe comprising thefirst sheath assembly 1, the connecting butt joint portion 60, and thetorque transmitting portion 9. The connecting butt joint portion 60 hasa first connecting portion 61 and a second connecting portion 62, andthe first connecting portion 61 is coaxially connected to the secondconnecting portion 62 detachably and fixedly. The second connectingportion 62 is detachably and fixedly connected to the first sheathassembly 1.

In some embodiments of the present invention, the first connectingportion and the second connecting portion realize a coaxial connectionin a manner of concave-convex abutting and pin fixing.

In some embodiments of the present invention, the constituent materialof the connecting butt joint portion is metal, and the constituentmaterial of the plug portion is a polymer. In some specific embodimentsof the present invention, the constituent material of the connectingbutt joint portion is stainless steel or copper, and the constituentmaterial of the plug portion is a polypropylene.

In some specific embodiments of the present invention, the firstultrasonic probe has a metal outer sleeve that is sleeved on the outersurface of the connecting butt joint portion, and the outer surface ofthe connecting butt joint portion is fitted to the inner surface of themetal outer sleeve, which is advantageous for enhancing the signaltransmission effect of the torque transmitting portion.

In some specific embodiments of the present invention, the firstultrasonic probe further has an insulating outer sleeve sleeved on theoutside of the metal sleeve to increase surface friction, and the innersurface of the insulating outer sleeve is fitted to the outer surface ofthe metal sleeve.

FIG. 6 is a structural view of a first ultrasonic probe of Embodiment 5of the present invention. FIG. 7 is a structural view of a firstconnecting portion shown in FIG. 6 .

With reference to FIGS. 1 and 6 , the first ultrasonic probe 6 has afirst connecting portion 61, a second connecting portion 62, and thefirst sheath assembly 1 which are sequentially connected. The secondsocket portion 62 is detachably and fixedly connected to the first plugportion 11.

With reference to FIG. 7 , the first connecting portion 61 has a springinner core 611, a bearing 613, a rotating portion 614, a sealing member615 and a protective casing 616 which are sequentially connected andcommunicated with each other, and a first positioning pin 617 and asecond positioning pin 618 disposed at a bottom portion of theprotective casing 616. The structure of the first positioning pin 617 isthe same as that of the second positioning pin 618. The sealing ring 612is sleeved on an outer surface of the spring inner core 611. The innerdiameter of the seal ring 612 is adapted to an outer diameter of thespring inner core 611, and the outer diameter of the seal ring 612 issmaller than the outer diameter of the bearing 613.

In the present embodiment, the first connecting portion 61 has a secondinner diameter for receiving the torque transmitting portion, the secondinner diameter being greater than or equal to 0.5 mm and larger than anouter diameter of the torque transmitting portion. With reference toFIG. 7 , an inner diameter of the spring inner core 611 is the secondinner diameter.

In some specific embodiments of the present invention, the second innerdiameter is any one of 0.5 mm, 1.0 mm, 1.2 mm, and 1.4 mm.

In some embodiments of the present invention, the spring inner core 611,the bearing 613, the rotating portion 614, and the sealing member 615have the same inner diameter.

With reference to FIGS. 2, 8 a and 8 b, the second connecting portion 62has a second locking portion 621 and a butt joint portion 622 which areboth in a hollow cylindrical structure and communicated with each otherinternally. A portion of the outer surface of the proximal end of thesecond locking portion 621 has a second threaded structure 6211. Thefirst threaded structure 1142 and the second threaded structure 6211 maybe engaged with each other, and the inner sidewall of the second lockingportion 621 has a tapered structure, so as to receive the first lockingportion 111 and is fitted to the outer sidewall of the first lockingportion 111 by taper self-locking.

In some embodiments of the present invention, the first locking portion111 is a hollow cylinder, and the inner diameter of the second lockingportion 621 is adapted to the outer diameter of the first lockingportion 111, so as to receive the first locking portion 111.

In some embodiments of the present invention, the inner diameter of thesecond locking portion 621 is 3 to 6 mm, and the length of the firstlocking portion 111 is equal to the length of the second locking portion621.

With reference to FIGS. 7, 8 a and 8 b, the length of the second lockingportion 621 is equal to a length of the spring inner core 611. The innerside wall of the butt joint portion 622 has an annular recess structure(not shown) which cooperates with the sealing ring 612, the bearing 613,the rotating portion 614 and the sealing member 615 to detachably andfixedly connect the first connecting portion 61 to the second connectingportion 62.

FIG. 9 is a structural view of a torque transmitting portion ofEmbodiment 5 of the present invention. With reference to FIG. 9 , thetorque transmitting portion 9 has a flexible sleeve 91, a metalprotection tube 92, a coaxial cable 93, and an ultrasonic transducer 94.The flexible sleeve 91 is a hollow metal spiral tube structure, and thecoaxial cable 93 passes through the inside of the flexible sleeve 91.One end of the metal protection tube 92 is fixed to the flexible sleeve91 by welding, and a signal line (not shown) and a shield line (notshown) of the coaxial cable 93 are fixedly connected to the twoelectrodes (not shown) of the ultrasonic transducer 94 by soldering orbonding. One side of the metal protection tube 92 is provided with amounting recess (not shown) for disposing the ultrasonic transducer 94.

With reference to FIGS. 1, 6 and 9 , the fixed end of the torquetransmitting portion 9 penetrates the spring inner core 611 and thebearing 613 to be fixed inside the rotating portion 614. The rotation ofthe rotating portion 614 drives the first positioning pin 617 and thesecond positioning pin 618 to rotate, so that the torque transmittingportion 9 transmits torque.

Embodiment 6

The present embodiment provides a second plug portion. The second plugportion has a main body portion, a third locking portion, and a secondsheath connecting portion.

FIG. 10 is a structural view of the second plug portion of the presentembodiment. FIG. 11 is a longitudinal sectional view of the second plugportion shown in FIG. 10 .

With reference to FIGS. 10 and 11 , the second plug portion 10 has amain body portion 101, a second sheath connecting portion 102, and athird locking portion 103. A second recess 1011 is defined in one end ofthe main body portion 101, and the third locking portion 103 of a hollowstructure is disposed at a bottom portion of the second recess 1011. Asilicone sealing ring 1014 is fixed to the inside of the main bodyportion 101. An outer sidewall of the main body portion 101 has fouranti-slip members 1012. An inner sidewall of the second recess 1011 isprovided with a third threaded structure 1013. An inside of the mainbody portion 101 communicates with an inside of the second sheathconnecting portion 102.

With reference to FIGS. 1, 8 a, 8 b and 11, a portion of the secondsheath connecting portion 102 is received inside the main body portion101, with one end being closely fitted to the silicone sealing ring1014. One end of the first sheath 121 is fixed inside the second sheathconnecting portion 102. On the one hand, the locking connection of thesecond locking portion 621 and the third locking portion 103 may berealized by rotating the main body portion 101 by holding the anti-slipmembers 1012. On the other hand, since a portion of an outer sidewall ofthe second sheath connecting portion 102 is closely fitted to a portionof an inner sidewall of the main body portion 101 and is rotatablerelative to the main body portion 101, the second sheath connectingportion 102 may be prevented from rotating when the main body portion101 rotates, thereby avoiding the problem that the first sheath 121 istwisted and deformed.

While the embodiments of the present invention have been described indetail, it will be apparent to those skilled in the art that variousmodifications and changes can be made to the embodiments. However, it isto be understood that such modifications and variations are within thescope and spirit of the present invention as described in the appendedclaims. Furthermore, the present invention described herein issusceptible to other embodiments and may be embodied or carried out invarious ways.

What is claimed is:
 1. A sheath assembly for an ultrasonic probe, theultrasonic probe is provided with a connecting butt joint portion and atorque transmitting portion, the sheath assembly comprising: a plugportion; and a sheath portion, wherein one end of the plug portion isused for detachably and fixedly connecting with the connecting buttjoint portion; a sheath connecting portion of the plug portion isfixedly connected to one end of the sheath portion; and an inside of theplug portion communicates with an inside of the sheath portion toreceive the torque transmitting portion, wherein the plug portion andthe sheath portion of the sheath assembly are connected to each other;the connecting butt joint portion is detachably and fixedly connected tothe plug portion; and a fixed end of the torque transmitting portion isfixedly connected in the connecting butt joint portion, and a transducerend of the torque transmitting portion extends through the connectingbutt joint portion and the plug portion to enter the sheath portion,wherein the plug portion comprises a first locking portion and a fixingportion, one end of the fixing portion defines a recess, one end of thefirst locking portion is fixed to a bottom portion of the recess, andthe inner sidewall of the recess has a first threaded structure torealize the detachably-fixed connection with the connecting butt jointportion through threaded engagement, and the first locking portionextends from the bottom portion of the recess and beyond an edge of thefirst threaded structure, the first locking portion has an internalhollow structure, and inside of the first locking portion communicateswith an inside of the sheath portion, and the first threaded structuresurrounds the first locking portion, the first locking portion is atruncated cone structure, and an outer sidewall of the first lockingportion has a taper shape, such that the first locking portion isreceived inside the connecting butt joint portion and is fixedlyconnected to the connecting butt joint portion by taper self-locking. 2.The sheath assembly for the ultrasonic probe of claim 1, wherein theplug portion comprises a recess, and an inner sidewall of the recess hasa first threaded structure to realize the detachably-fixed connectionwith the connecting butt joint portion through threaded engagement. 3.The sheath assembly for the ultrasonic probe of claim 2, wherein abottom portion of the recess is provided with a first locking portion,and an inside of the first locking portion communicates with an insideof the sheath portion; an outer sidewall of the first locking portion isengageable with an inner sidewall of the connecting butt joint portion,such that the first locking portion is received inside the connectingbutt joint portion.
 4. The sheath assembly for the ultrasonic probe ofclaim 3, wherein the first locking portion has a first inner diameterfor receiving the torque transmitting portion, the first inner diameterbeing greater than or equal to 0.5 mm and larger than an outer diameterof the torque transmitting portion.
 5. The sheath assembly for theultrasonic probe of claim 3, wherein the outer sidewall of the firstlocking portion has a taper such that the first locking portion isreceived inside the connecting butt joint portion and is fixedlyconnected to the connecting butt joint portion by taper self-locking. 6.The sheath assembly for the ultrasonic probe of claim 5, wherein thetaper ranges from 3 degrees to 6 degrees to enable the sheath assemblyto withstand at least 1 atmosphere for a time period of at least 30seconds.
 7. The sheath assembly for the ultrasonic probe of claim 3,wherein the plug portion has a sealing portion for detachably andfixedly connecting to the first locking portion.
 8. The sheath assemblyfor the ultrasonic probe of claim 1, wherein the other end of the sheathportion has a sealing head structure.
 9. The sheath assembly for theultrasonic probe of claim 1, wherein the sheath portion has a firstsheath and a second sheath connected to each other, one end of the firstsheath being fixedly connected to the sheath connecting portion of theplug portion, the first sheath having a Shore hardness greater than aShore hardness of the second sheath.
 10. The sheath assembly for theultrasonic probe of claim 9, wherein the sheath portion further has athird sheath, and the third sheath has a Shore hardness greater than orequal to the Shore hardness of the first sheath and is at leastpartially sleeved outside the first sheath to enhance a strength of thesheath portion.
 11. The sheath assembly for the ultrasonic probe ofclaim 10, wherein one end of the third sheath is fixedly connected tothe sheath connecting portion, and is sleeved outside the first sheath,the third sheath having a length less than a length of the first sheath.12. The sheath assembly for the ultrasonic probe of claim 11, whereinthe Shore hardness of the first sheath is 50D-90D, the Shore hardness ofthe second sheath is 30D-75D, and the Shore hardness of the third sheathis 50D-90D.
 13. The sheath assembly for the ultrasonic probe of claim10, wherein the third sheath is a metal spring sleeve, and the metalspring sleeve is movably sleeved outside the sheath connecting portionand a portion of the first sheath.